From March 3, the company will offer an in-car 4G LTE data plan for $20 a month. The plan will see an OnStar Wi-Fi hotspot fitted in vehicles that connect to the internet via LTE. The hotspot will allow up to seven devices to be connected to it at one time. Chevy says it is offering the unlimited data plan because in-car data use had grown so fast, jumping 200% last year, reports the BBC.